From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
The despatch and testing of half watt lamps for a car's lighting system.
| Identifier | ExFiles\Box 38\3\ Scan258 | |
| Date | 23th April 1920 | |
| R.R. 235A (100 T) (R.H. 79a 10-12-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2947 X3362 To R.{Sir Henry Royce} from EFC. c. to CJ. c. to E.{Mr Elliott - Chief Engineer} EFC3/T23.4.20. X.1114. HALF WATT LAMPS. X.3362. We are having despatched to you under separate cover two B.T.H. 24 watt half watt type lamps for you to try out on your lighting installation. These lamps, although marked 12 volt for a 12 volt car lighting system, have really been made for a normal voltage of 14 and should, therefore, be slightly less brilliant than previous 12 volt lamps on the same voltage. We have four more of these lamps, two of which we are putting on our vibration test of lamps and the other two of which we are putting in the head lamps of a car for trial. Our object is to prove that half watt lamps are suitable for such a purpose, if not too highly over-run. There will then be the advantage of the smaller current consumption of these lamps. EFC. | ||